//抖动动作
//用法：使节点抖动
cc.Shake = function(time, range){
	var coord = { x : 0, y : 0};
	var shake = null;
	for (var i = 0; i < 4; i++){
		var x = 0;
		var y = 0;
		if (i < 3){
			var dis_tmp = Math.random() * range;
			var rad = Math.random() * 2 * Math.PI;
			x = Math.round(dis_tmp * Math.cos(rad));
			y = Math.round(dis_tmp * Math.sin(rad));
		}
		
		var moveby = cc.moveBy(time / 6, x - coord.x, y - coord.y);
		if (shake == null){
			shake = cc.sequence(moveby);
		}else{
			shake = cc.sequence(shake, moveby);
		}

		coord = {x : x, y : y};
	}
	return shake;
};
cc.shake = function(...args) {
	return new cc.Shake(...args);
}